Induction coil and mounting therefor



Patented Dec. 28, 1925.

lrlltllTED STATES PATENT OFFICE.

RALPH A. CLARKE, OF WORCESTER, MASSACHUSETTS, ASSIGNOR TO STANDARD RADIOCORPORATTON, OF WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSA-CHUSETTS.

INDUCTION COIL AND MOUNTING THEREFOR.

Application filed August 15, 1924. Serial No. 732,200.

This invention relates to an improved in These plates have a successionof holes 4 duction coil and mountingl for use in radio in alinement withthe corresponding holes apparatus, and is particularly directed to 4t inthe mount l for the spider web coil. the mechanical safeguarding oit thecoil The bolts 5 are passed through these holes 5 winding. and areprovided with the preferably non- One of the objects of this inventionis to magnetic spacing washers or nuts (l to main- 60 provide aprotective system for in ductaiice tain the face plates at a distancefrom the coils which renders them free from danger turns of wire 7. Theends oit the coil are ot mechanical abrasion, or of short circuitingappropriately brought to the bolts and l by Contact with loose leadswithin the ap- Clampett in place, to permit the bolts to act paratus. as.terminals for the coil. A central hole (in Other objects of thisinvention will be rllt is provided in each of the face plates inapparent in the Cours@ 0f the. following* aliiflelielt QWll'li a liOlel0 iii tlie HiOuiit, l, gpccicution for fasteningthe assembly to a panelor l .ln the accompanying); drawingzsbaseboard l.

Fig. 1 represents a plan of the exterior 0f In constructing a coal andmount ot this T one of my improved coil mounts and protype for a superlieterodyne apparatus, the

tact-ors; inductance coil 7 must be provided with sev- 4i), if; a @msgSection 0n the 1in@ 2 4), eral taps to enable a connection to the gridor l. fastened to a baseboard; and plate of the oscillating' tube, orfor tap- Finj. 8 is a plan of a coil mount and proping off in tuning'the primary circuit. This 75 rector having a. number of taps, apparatusis particularly adapted for use ,llt is well known that in radioapparatus II Such CICUS by bringing; the lill) WTPS 7 as constructed atthe present time, the induclO lhSIGSPGClV@ l)OlrS and SeCUllDl them b5"2.5 tance coils employed must be made very com- Clamping. The ends otthe bolts are pro`r m0@ and must. ft in Closely Confined Spaces videdwith binding screw-heads 8, to enable so in Order t0 reduc@ the totalSig@ 0f the cabiconnection of the assembled coil in the cirnet to withinreasonable limits. Cuit- One of the types of inductanc-es capable It l5preferable: lll Order t0 lflC-lllrar@ 3S' :io of use in such apparatusior short wave Sell'lllly 0r the ser ro lrllrl lll@ far@ lll-lll@ 2lengths is that known as the spider web Wlr'll, lrlrllcll 9 t()lrlllcll@ the Prolll' 00W 85 coil. This comprises a supporting mountnecrlorrs 1n the Clrclllrot insulating; material having an odd num- IClllllll l 1 ber ot circumferentially spaced arms. and Ill ,il lllollrltlor all lllrfllclllllc'@ Crlllfl the inductance wire is woundsuccessively Pall' of lace Plates COlXl l Wlrll lllrllllfrl-'rlllftl inand out of these arms, to produce the to rll@ @O llaslllllltlllerllllllQ'lWfell Sfllrl Plllles 9U spider web eitect. This coil. hasthe advan* and sind .Colla Clllllllllll lllQflrlS llrlgsllli' Offseipgufatnlg the turns of ripe having through btlild ail/ld' S21-ld @Cdl't0 l'lOlCl th@ a ment dig-www5 of potential; in this Wav same ininvariable rigid. relation. the ends 4o large capacitive effects areavoided` as these 0r lille Wlrlfllng 0l Slld Coll llllg elecrrlcllllyarlkuokfn to WHW with the difference in connected to individuals ot saidclamping potential and the distance of separation of means; andlerllllllll conller/llllg (lll Sal-Cl 'the sev-eral turns. It has.however. the xgreat Clamlllllg lllenrls external t0 Srlrl lll'lldisadvantage of not beingi mechanically Yrigid 2 Ill lrl lrlrlllctlllcellrllt: l sllppflrtlllg SP1' :i5 in its construction, and of being verymuch der llavlllg a Coll lllereollg lr Pim 0l' fac@ Subject tomechanical abmsio by impl@ plates mounted coaxial with and xparallel..ments used in construction. This abrasion t0 the Sad Slllder: SPClrlgWlSllerS lor Salm gives rise to .short circuits between the turns ratlngSlrlrl Plales mfr-Sarl, COlL (flllllllllll themselves, or even to shortcircuits between bolt Dilssmg throughsmd splder Sflld Plates 50 thewires of the several turns, and another Mld Srlld Washers: Sfllfl llOlrSSerfllll ils rer* Conductor in the apparatug ininals for 'said unit, andelectrical'connec- 10i To avoid these difficulties in the present tionsestablished between said winding and apparatus, two face plates 2 and 8are dis- Sillrl bolts between sind plaines' posed on opposite faces ofthe coil support l. 3- lll all mdllCallC a Coll lllVlrlg il Pill` ralityof windings with taps from the ends of the windings, a support toi'vsaid coil, a face plate pa'allel to said support and held in .spacedrelation therewith, metallic Clamping means passing through said supportand said pla-te to hold the Seme in invariable 1e lation, the number ofsaid clamping means loeing` greater than the number of windings in saidcoil, .Said tape 'being connecte-:l each to one of Said clamping meansand terminal l0 connectors on seid Clamping means external to saidplate.

In testin'iony whereof, atiix my signa1 ture.

RALPH En CLA?. .Kill

